1. Technical Field
The present invention relates to data processing systems and, in particular, to message based windowing systems. Still more particularly, the present invention provides a method, apparatus, and program for dynamic expansion and overlay of controls in a message based windowing system.
2. Description of Related Art
Users with vision impairment require mechanisms for increasing their ability to read and recognize content on a computer screen or similar presentation device. Existing methods include system enlargement of fonts and magnification utilities that enlarge selected content on the screen. Both of these solutions have disadvantages.
A side effect of increasing system fonts is that the amount of viewable content on the screen is reduced. Furthermore, the layout of presentation controls may be degraded, since applications are often designed for more common font sizes.
In the case of magnification utilities, the user may be forced to accept degraded, i.e. pixilated, text and graphics presentation for the magnified area. This results in loss of clarity and may reduce recognition of graphical content. Magnifiers also require overt action on the part of the user in order to direct and control the magnified area.
Even for those without significant vision impairment, it may often be difficult to read a particular part of a form. For example, in low light situations or in cases where high screen resolutions are preferred, presentation size of on-screen controls may be reduced.
Therefore, it would be advantageous to provide a mechanism for improving recognition and readability of screen content.